The present invention relates to rail maintenance equipment, and specifically to maintenance equipment for removing ballast from a railway track bed and moving a railroad tie located on the track bed.
It is known to provide a machine for clearing the ballast from a crib (space between adjacent ties) in a railway track by repeatedly pushing the ballast from the center of the track laterally outwardly by two different arms or to provide a machine for clearing the ballast from a crib by pushing the ballast completely from one side of the track to the other. These known machines are described in U.S. Pat. Nos. 1,588,801; 1,691,933; 2,743,539; 2,846,206; 3,553,859; 3,826,195; 3,948,185; 5,046,270; 5,125,345; 5,907,914; 5,926,981; and 6,598,325. While in some situations, it is desirable to remove all of the ballast to one side or the other, and in other situations it is desirable to remove the ballast to both sides in relatively equal amounts, no machines are provided that allow the operator to choose between these different clearing options. That is, known machines either clear to one side or the other, or else only clear from the middle outwardly.
Also, while some machines are provided with a tool for engaging and moving the ballast under the track itself, such tools are configured for use specifically with the particular machine they are designed for.
The known cribbing machines are provided with manual controls for moving the various arms and tools, but are not provided with electronic controls that limit the movement of the frames, arms and tools to prevent the frames, arms and tools from striking the track as the ballast is being removed.
Further, once the ballast has been cleared away from the tie, the known machines are not equipped to move the tie, and instead, a different machine is required for that step of the process.